Research Summary - 4
Prolonged birth makes it worse—labor duration impacts postpartum systemic inflammation in dairy cows
| Date/Time: |
9/13/2025
14:30
|
| Author: |
Jess McArt |
| Clinic: |
Cornell University |
| City, State, ZIP: |
Ithaca, NY 14853 |
Markus Guttler, BS
1
;
Jackson A. Seminara, BS
2
;
Kate C. Creutzinger, MS, PhD
3
;
Heather M. Dann, MS, PhD
4
;
Katy L. Proudfoot, MS, PhD
5
;
Jessica A. A. McArt, DVM, PhD, DABVP (Dairy Practice)
2
;
1Faculty of Veterinary Medicine, University of Leipzig, Leipzig, Germany
2Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853
3Department of Animal and Veterinary Sciences, University of Vermont, Burlington, VT, 05405
4William H. Miner Agricultural Research Institute, Chazy, NY, 12921
5Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PEI, Canada
Introduction:
Parturition initiates the most challenging phase in a dairy cow’s life, as early lactation is crucial for successful milk production and cow welfare. Dystocia, defined as prolonged labor or labor that required direct assistance, can disrupt physiological processes during the transition into lactation, resulting in increased disease incidence disease and herd removal, reduced fertility, and loss of milk yield. Risk factors for dystocia requiring assistance are well documented, yet those for prolonged labor are largely unknown. Although the pathophysiological link from prolonged labor to postpartum disease remains poorly understood, we know that systemic inflammation during early postpartum is a common occurrence and often a sign of lactational maladaptation. As labor is generally associated with stress and tissue trauma, our hypothesis was that prolonged labor would be associated with a greater systemic inflammatory response.
Materials and methods:
We based our exploratory analysis on data from Creutzinger et al. (2021), in which 95 multiparous Holstein cows were housed on a single dairy farm in New York and assigned randomly to 4 different maternity pen types with low or high stocking density with or without a blind. Labor duration, determined from video footage, was defined as the time from initial abdominal contraction until expulsion of calf hips from the dam. To evaluate the severity of systemic inflammation, we used serum haptoglobin concentration measured at 7 timepoints relative to calving: -21, -14, -7 ± 3 d prepartum and 3, 7, 10, and 14 ± 1 d postpartum. We created linear mixed models using the fixed effects of labor duration, parity group (entering parity 2, 3, ≥4), maternity pen type, day, a quadratic labor duration term, all 2-way interactions, and the random effect cow. Pre- and postpartum models were fit separately, with postpartum models including the additional fixed effects of calf weight and postpartum calcium treatment. A backwards stepwise elimination process was used to test and eliminate any variable models where P > 0.1. Outcomes were calculated using the final models by comparing predicted cows at the 20th (43 min) and 80th (100 min) quantiles of labor duration times.
Results:
Data from 95 cows were used including n = 44 parity 2, n = 30 parity 3, and n = 21 parity ≥4 cows. Median labor duration was 65 min (1st quartile = 47 min, 3rd quartile = 89 min) with a range from 24 to 200 min. Haptoglobin concentration did not differ prepartum based on labor duration (P = 0.69). Postpartum, haptoglobin concentration differed at 3 and 7 d after calving between cows with shorter (43 min) and longer (100 min) labor duration (both P < 0.05). At 3 d postpartum, mean haptoglobin concentration was elevated in cows with long labor duration (0.56 g/L, 95% CI = 0.49 to 0.66 g/L) compared to those with short labor duration (0.39 g/L, 95% CI = 0.45 to 0.34). At 7 d postpartum, mean haptoglobin concentration remained elevated in cows with long labor duration (0.41 g/L, 95% CI = 0.35 to 0.49 g/L) compared to those with short labor duration (0.30 g/L, 95% CI = 0.26 to 0.35).
Significance:
Prolonged labor duration is associated with early postpartum inflammation. Given the association of elevated haptoglobin with negative health outcomes, labor duration might serve as an early indicator of early lactation complications, allowing immediate preventive care. Although our study was exploratory using data from a single farm setting that was not originally designed to answer this question, these preliminary results support additional research into the factors affecting labor duration as well as investigation of therapeutic plans to minimize the negative impacts of excessive inflammation postpartum.
